New color stuff

- CMYK function
- More default colors
- Interpret RGB values as sRGB

1 files changed, 100 insertions, 8 deletions

diff --git a/src/geom/paint.rs b/src/geom/paint.rs
index f8638656..7342024c 100644
--- a/src/geom/paint.rs
+++ b/src/geom/paint.rs
@@ -26,12 +26,44 @@ where
 pub enum Color {
     /// An 8-bit RGBA color.
     Rgba(RgbaColor),
+    /// An 8-bit CMYK color.
+    Cmyk(CmykColor),
+}
+
+impl Color {
+    pub const BLACK: Self = Self::Rgba(RgbaColor::new(0x00, 0x00, 0x00, 0xFF));
+    pub const GRAY: Self = Self::Rgba(RgbaColor::new(0xAA, 0xAA, 0xAA, 0xFF));
+    pub const SILVER: Self = Self::Rgba(RgbaColor::new(0xDD, 0xDD, 0xDD, 0xFF));
+    pub const WHITE: Self = Self::Rgba(RgbaColor::new(0xFF, 0xFF, 0xFF, 0xFF));
+    pub const NAVY: Self = Self::Rgba(RgbaColor::new(0x00, 0x1f, 0x3f, 0xFF));
+    pub const BLUE: Self = Self::Rgba(RgbaColor::new(0x00, 0x74, 0xD9, 0xFF));
+    pub const AQUA: Self = Self::Rgba(RgbaColor::new(0x7F, 0xDB, 0xFF, 0xFF));
+    pub const TEAL: Self = Self::Rgba(RgbaColor::new(0x39, 0xCC, 0xCC, 0xFF));
+    pub const EASTERN: Self = Self::Rgba(RgbaColor::new(0x23, 0x9D, 0xAD, 0xFF));
+    pub const PURPLE: Self = Self::Rgba(RgbaColor::new(0xB1, 0x0D, 0xC9, 0xFF));
+    pub const FUCHSIA: Self = Self::Rgba(RgbaColor::new(0xF0, 0x12, 0xBE, 0xFF));
+    pub const MAROON: Self = Self::Rgba(RgbaColor::new(0x85, 0x14, 0x4b, 0xFF));
+    pub const RED: Self = Self::Rgba(RgbaColor::new(0xFF, 0x41, 0x36, 0xFF));
+    pub const ORANGE: Self = Self::Rgba(RgbaColor::new(0xFF, 0x85, 0x1B, 0xFF));
+    pub const YELLOW: Self = Self::Rgba(RgbaColor::new(0xFF, 0xDC, 0x00, 0xFF));
+    pub const OLIVE: Self = Self::Rgba(RgbaColor::new(0x3D, 0x99, 0x70, 0xFF));
+    pub const GREEN: Self = Self::Rgba(RgbaColor::new(0x2E, 0xCC, 0x40, 0xFF));
+    pub const LIME: Self = Self::Rgba(RgbaColor::new(0x01, 0xFF, 0x70, 0xFF));
+
+    /// Convert this color to RGBA.
+    pub fn to_rgba(self) -> RgbaColor {
+        match self {
+            Self::Rgba(rgba) => rgba,
+            Self::Cmyk(cmyk) => cmyk.to_rgba(),
+        }
+    }
 }
 
 impl Debug for Color {
     fn fmt(&self, f: &mut Formatter) -> fmt::Result {
         match self {
             Self::Rgba(c) => Debug::fmt(c, f),
+            Self::Cmyk(c) => Debug::fmt(c, f),
         }
     }
 }
@@ -59,19 +91,13 @@ pub struct RgbaColor {
 }
 
 impl RgbaColor {
-    /// Black color.
-    pub const BLACK: Self = Self { r: 0, g: 0, b: 0, a: 255 };
-
-    /// White color.
-    pub const WHITE: Self = Self { r: 255, g: 255, b: 255, a: 255 };
-
     /// Construct a new RGBA color.
-    pub fn new(r: u8, g: u8, b: u8, a: u8) -> Self {
+    pub const fn new(r: u8, g: u8, b: u8, a: u8) -> Self {
         Self { r, g, b, a }
     }
 
     /// Construct a new, opaque gray color.
-    pub fn gray(luma: u8) -> Self {
+    pub const fn gray(luma: u8) -> Self {
         Self::new(luma, luma, luma, 255)
     }
 }
@@ -155,6 +181,72 @@ impl Display for RgbaError {
 
 impl std::error::Error for RgbaError {}
 
+/// An 8-bit CMYK color.
+#[derive(Copy, Clone, Eq, PartialEq, Hash)]
+pub struct CmykColor {
+    /// The cyan component.
+    pub c: u8,
+    /// The magenta component.
+    pub m: u8,
+    /// The yellow component.
+    pub y: u8,
+    /// The key (black) component.
+    pub k: u8,
+}
+
+impl CmykColor {
+    /// Construct a new CMYK color.
+    pub const fn new(c: u8, m: u8, y: u8, k: u8) -> Self {
+        Self { c, m, y, k }
+    }
+
+    /// Construct a new, opaque gray color as a fraction of true black.
+    pub fn gray(luma: u8) -> Self {
+        Self::new(
+            (luma as f64 * 0.75) as u8,
+            (luma as f64 * 0.68) as u8,
+            (luma as f64 * 0.67) as u8,
+            (luma as f64 * 0.90) as u8,
+        )
+    }
+
+    /// Convert this color to RGBA.
+    pub fn to_rgba(self) -> RgbaColor {
+        let k = self.k as f32 / 255.0;
+        let f = |c| {
+            let c = c as f32 / 255.0;
+            (255.0 * (1.0 - c) * (1.0 - k)).round() as u8
+        };
+
+        RgbaColor {
+            r: f(self.c),
+            g: f(self.m),
+            b: f(self.y),
+            a: 255,
+        }
+    }
+}
+
+impl Debug for CmykColor {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        let g = |c| c as f64 / 255.0;
+        write!(
+            f,
+            "cmyk({:.1}%, {:.1}%, {:.1}%, {:.1}%)",
+            g(self.c),
+            g(self.m),
+            g(self.y),
+            g(self.k),
+        )
+    }
+}
+
+impl From<CmykColor> for Color {
+    fn from(cmyk: CmykColor) -> Self {
+        Self::Cmyk(cmyk)
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;